According to [this thread](https://www.reddit.com/r/Overwatch/comments/4sfwlk/what_game_mode_is_koth/), Timmy Jim's comment is correct that Control is what people refer to as King of the Hill.

>Control is KOTH

> Control

>KOTH is King Of The Hill, so it's control.

The term is defined [here](http://www.giantbomb.com/king-of-the-hill/3015-1292/) as the following:

>King of the Hill is a popular game mode where the players have to stay in a designated area of a map to gain points. This mode is becoming increasingly popular in shooters.

In terms of Overwatch, Control is described [here](http://overwatch.gamepedia.com/Control):

>Once the match has started and both teams have left the spawn, the control point takes 30 seconds to unlock. Once it unlocks, the objective area can be captured by either team. To capture the checkpoint, members of only one team must stand on the point for a given time, speed increasing with the number of teammates present. Once captured, the team must defend the point, while the other must gain control of the area by driving the enemies out and capturing it themselves.

Thus, Control very much fits into the King of the Hill definition. The maps used for this game mode are [Nepal][1], [Lijang Tower][2], [Ilios][3], and [Oasis][4].

----------


As for where this term came from, [Wikipedia](https://en.wikipedia.org/wiki/King_of_the_Hill_(game)) says it is a children's game, including an excerpt from [this panel](https://en.wikipedia.org/wiki/Children%27s_Games_(Bruegel)) created in 1560. Thus, "King of the Hill" is quite an old term.

[1]:http://overwatch.gamepedia.com/Nepal
[2]:http://overwatch.gamepedia.com/Lijiang_Tower
[3]:http://overwatch.gamepedia.com/Ilios
[4]:http://overwatch.gamepedia.com/Oasis